1. Field of the Invention
This invention relates to a novel endo-xyloglucan transferase responsible for the growth of plant cell wall, gene coding for said enzyme isolated from a plant, a method of transferring xyloglucan molecules by using said enzyme.
2. Description of Related Art
Xyloglucan (hereinafter referred to simply as XG) is the major component of plant cell wall wherein XG binds to the surface of cellulose microfibrils and cross-links them into a complex network. Although it is believed that the splitting and reconnection of XG cross links are required for wall construction and reconstruction, the mechanism therefor has not been elucidated so far.
Albersheim hypothesized a mechanism for the reconstruction of XG through the function of some endo-transglycosylase [Plant Biochemistry, (1976), Academic Press, 225-274].
The present inventors previously examined an extract obtained from the apoplast (extra-plasma membrane section of plant consisting of cell wall and cell space) of epicotyls of Vigna angularis seedlings, a bean plant, and, as a result, found out that a fraction precipitated between 20% and 80% saturation of ammonium sulfate would enhance the polydispersity of XG molecules [Nishitani et al., Physiologia Plantarum, 82, 490-497 (1991)].
However, there has been identified no substance responsible for the reconstruction of XG molecules and the polydispersity of the molecular weight thereof. Further, no detailed mechanism therefor has been elucidated so far.